ZFS on 4x2TB post install

[Adnan]

I have a server at SoYouStart (OVH), and I don't have access to the installation, according to the support, even through the KVM IP, I won't have access. And I'm a ZFS noob.

So, I have 4x2TB. I must have /, swap and /var/lib/vz, I can choose whatever size I want for them, I can install them only on the first disk or in softRAID 1, 5, 10. With 4 HDD it would be great to use RAIDz1, 1 disk fault tolerance but I'm planning on having a second server for backups and FS synchronisation, so I think the chances of having 2 HDD failing at the same time and me having no backups is negligible.

Is there a way to use the 4 HDD to make a RAIDz1 with proxmox (post install) or as the OS is installed on the first HDD, I can only use the 3 others?

 

[ph0x]

Raidz is not recommended for VM images, you should go for a striped mirror (aka raid10). So they install proxmox for you? Why can't they choose zfs raid10?

 

[Adnan]

Raidz is not recommended for VM images, you should go for a striped mirror (aka raid10). So they install proxmox for you? Why can't they choose zfs raid10?

Please explain why Raidz isn't recommended for VM images, Proxmox' wiki doesn't state anything about it (or I didn't see it yet).

Regarding installation, you choose your distribution, you "make" your HDD layout on their HTML page, and you click "install". They do an unattended install and you receive an email when it's done. As their web page is standard for all distribution, I can't choose ZFS so they can't install it "automatically"

 

[ph0x]

I see. Although I haven't read anything about setting up zfs after installation, I guess this is rather complicated because you have to play around with initramfs. But maybe someone else has a guide for that.

Raidz is not recommended because of the parity calculations slowing down your small IOPS of spinning disks even more.
See the performance section of the documentation.

 

[ness1602]

Raidz is okay, but the write speed should be lower than raid10, that's why usually people don't recommend it. I'm using Raidz with zfs on almost all OMV servers.

 

[Adnan]

I see. Although I haven't read anything about setting up zfs after installation, I guess this is rather complicated because you have to play around with initramfs. But maybe someone else has a guide for that.

Currently, I installed Proxmox and its local storage on disk 1, and post install I created a zpool on disks 2, 3 and 4.

Raidz is not recommended because of the parity calculations slowing down your small IOPS of spinning disks even more.
See the performance section of the documentation.

I see. According to this post and the authors advices, I wanted to take advantage of FS snapshots, ZFS seems to be the FS of any admin's dream. I'm still in a test env, so I will make some tests and see if the speed is acceptable.

Raidz is okay, but the write speed should be lower than raid10, that's why usually people don't recommend it. I'm using Raidz with zfs on almost all OMV servers.

I hijack my own post, would you recommend OMV above another NAS distribution? My needs are only some windows shares.

 

[ph0x]

The hypervisor itself could be hosting samba shares and utilize zfs snapshots as windows shadow copies at the same time.

 

[Dunuin]

Raidz is okay, but the write speed should be lower than raid10, that's why usually people don't recommend it. I'm using Raidz with zfs on almost all OMV servers.

Depends on your workload. If you got alot of random writes your HDDs will be the bottleneck raid10 would allow more IOPS compared to raidz. And you need to increase the volblocksize to atleast 32K and cant use 8K anymore if you don't want to waste 1/3 of your capacity. Thats again bad for small writes.

 

[ness1602]

Currently, I installed Proxmox and its local storage on disk 1, and post install I created a zpool on disks 2, 3 and 4.


I see. According to this post and the authors advices, I wanted to take advantage of FS snapshots, ZFS seems to be the FS of any admin's dream. I'm still in a test env, so I will make some tests and see if the speed is acceptable.


I hijack my own post, would you recommend OMV above another NAS distribution? My needs are only some windows shares.

It is really easy to configure everything inside it's GUI,and it is Debian based. Really enough for me.